Abstract: 　Objective To study genomic polymorphic DNA and genetic distance of 7 species of ticks. Methods Ticks used in this study were Dermacentor nuttalli, D.silvarum, Haemaphysalis qinghaiensis, H.formosensis, H.punctata, Amblyomma testudinarium, and Ixodes ovatus. DNA extracts of the 7 species of ticks were amplified by random amplified polymorphic DNA (RAPD) and PCR technique using 5 primers with different arbitrary single chain polynucleotide sequences. DNA fingerprint maps were analyzed and the genetic distance among 7 species of ticks were counted. Results The amplified products of the 7 species of ticks by RAPD all showed their specific DNA band. The average genetic distance among them was 071. Conclusion RAPD can differentiate the 7 species of ticks.

Key words: Ticks, Genome, Random amplified polymorphic DNA technique(RAPD), Variation (Genetics), Cluster analysis